Off-Line Coupling of Capillary Electrophoresis to Substrate-Assisted Laser Desorption Inductively Coupled Plasma Mass Spectrometry

Peš, Ondřej; Jungová, Pavla; Vyhnánek, Radek; Vaculovič, Tomáš; Kanický, Viktor; Preisler, Jan

doi:10.1021/ac801036x

Cited by 27 publications

(20 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In most reports on dried-droplet sample preparation in combination with laser ablation, the smallest possible dried sample residues were sought for [13–22] . Small spots can be ablated completely with only a few laser shots.…”

Section: Resultsmentioning

confidence: 99%

Radial line-scans as representative sampling strategy in dried-droplet laser ablation of liquid samples deposited on pre-cut filter paper disks

Nischkauer¹,

Vanhaecke²,

Bernacchi³

et al. 2014

Spectrochimica Acta Part B: Atomic Spectroscopy

View full text Add to dashboard Cite

Nebulising liquid samples and using the aerosol thus obtained for further analysis is the standard method in many current analytical techniques, also with inductively coupled plasma (ICP)-based devices. With such a set-up, quantification via external calibration is usually straightforward for samples with aqueous or close-to-aqueous matrix composition. However, there is a variety of more complex samples. Such samples can be found in medical, biological, technological and industrial contexts and can range from body fluids, like blood or urine, to fuel additives or fermentation broths. Specialized nebulizer systems or careful digestion and dilution are required to tackle such demanding sample matrices. One alternative approach is to convert the liquid into a dried solid and to use laser ablation for sample introduction. Up to now, this approach required the application of internal standards or matrix-adjusted calibration due to matrix effects. In this contribution, we show a way to circumvent these matrix effects while using simple external calibration for quantification. The principle of representative sampling that we propose uses radial line-scans across the dried residue. This compensates for centro-symmetric inhomogeneities typically observed in dried spots. The effectiveness of the proposed sampling strategy is exemplified via the determination of phosphorus in biochemical fermentation media. However, the universal viability of the presented measurement protocol is postulated. Detection limits using laser ablation-ICP-optical emission spectrometry were in the order of 40 μg mL− 1 with a reproducibility of 10 % relative standard deviation (n = 4, concentration = 10 times the quantification limit). The reported sensitivity is fit-for-purpose in the biochemical context described here, but could be improved using ICP-mass spectrometry, if future analytical tasks would require it. Trueness of the proposed method was investigated by cross-validation with conventional liquid measurements, and by analyzing IAEA-153 reference material (Trace Elements in Milk Powder); a good agreement with the certified value for phosphorus was obtained.

show abstract

Section: Resultsmentioning

confidence: 99%

Radial line-scans as representative sampling strategy in dried-droplet laser ablation of liquid samples deposited on pre-cut filter paper disks

Nischkauer¹,

Vanhaecke²,

Bernacchi³

et al. 2014

Spectrochimica Acta Part B: Atomic Spectroscopy

View full text Add to dashboard Cite

show abstract

“…Cells were harvested and cell lysates prepared as described previously [39]. Briefly, pelleted cells were washed twice with 1 × PBS and 1.0 × 10 6 cell were lysed in a mixture of 3 M HCl/10% trichloroacetic acid at room temperature for 3 h followed by incubation at 70 °C for 5 h. The lysate was centrifuged (600 g/5 min) to remove cell debris and the total amount of copper in supernatant was determined by substrate-assisted laser desorption inductively-coupled plasma mass spectrometry (SALD ICP MS) [40]. …”

Section: Methodsmentioning

confidence: 99%

Wedelolactone Acts as Proteasome Inhibitor in Breast Cancer Cells

Nehybová

Šmarda

Daniel

et al. 2017

IJMS

Self Cite

View full text Add to dashboard Cite

Wedelolactone is a multi-target natural plant coumestan exhibiting cytotoxicity towards cancer cells. Although several molecular targets of wedelolactone have been recognized, the molecular mechanism of its cytotoxicity has not yet been elucidated. In this study, we show that wedelolactone acts as an inhibitor of chymotrypsin-like, trypsin-like, and caspase-like activities of proteasome in breast cancer cells. The proteasome inhibitory effect of wedelolactone was documented by (i) reduced cleavage of fluorogenic proteasome substrates; (ii) accumulation of polyubiquitinated proteins and proteins with rapid turnover in tumor cells; and (iii) molecular docking of wedelolactone into the active sites of proteasome catalytic subunits. Inhibition of proteasome by wedelolactone was independent on its ability to induce reactive oxygen species production by redox cycling with copper ions, suggesting that wedelolactone acts as copper-independent proteasome inhibitor. We conclude that the cytotoxicity of wedelolactone to breast cancer cells is partially mediated by targeting proteasomal protein degradation pathway. Understanding the structural basis for inhibitory mode of wedelolactone might help to open up new avenues for design of novel compounds efficiently inhibiting cancer cells.

show abstract

“…As a control, the cells were treated with DMSO. Pelleted cells were washed twice with 1X PBS, counted in hemocytometer and lysed in a mixture of 3 N HCl and 10% trichloroacetic acid (12) at room temperature for 3 h followed by incubation at 70˚C for 5 h. The lysate was centrifuged (600 g/5 min) to remove cell debris and the total amount of copper in supernatant was determined by substrate-assisted laser desorption inductively-coupled plasma mass spectrometry (SALD ICP MS) (23). Each sample was mixed with 40 μM aqueous solution of rhodamine B in a 1:3 volume ratio for spot visualization and spotted onto a polyethylene terephthalate glycol plate as a 200-nl droplet in five replicates.…”

Section: Dna Fragmentation Analysismentioning

confidence: 99%

Copper ions regulate cytotoxicity of disulfiram to myeloid leukemia cells

Navrátilová

Jungová²,

Vaňhara³

et al. 2009

Int J Mol Med

View full text Add to dashboard Cite

Abstract. White blood cell (WBC) count is considered a prognostic risk factor in acute myeloid leukemia. As density of leukemic cells increases, the cytotoxic activity of certain anticancer drugs, such as vincristine and doxorubicin, progressively decreases. In this study, we investigated the cell density-dependent induction of apoptosis of human acute myeloid leukemia U937 and ML-1 cells by disulfiram (DSF), the dithiocarbamate drug recently proposed for treatment of human cancers. This effect is dependent on uptake of extracellular copper and its intracellular accumulation. Highdensity cells cannot uptake and accumulate this metal to a sufficient level that would allow induction of apoptosis due to progressive decrease of its extracellular concentration. Simple addition of copper can resume sensitivity of highdensity leukemic cells to DSF and improve efficiency of antileukemic therapies using this drug, thus providing benefit to patients with high WBC count.

show abstract

Off-Line Coupling of Capillary Electrophoresis to Substrate-Assisted Laser Desorption Inductively Coupled Plasma Mass Spectrometry

Cited by 27 publications

References 57 publications

Radial line-scans as representative sampling strategy in dried-droplet laser ablation of liquid samples deposited on pre-cut filter paper disks

Radial line-scans as representative sampling strategy in dried-droplet laser ablation of liquid samples deposited on pre-cut filter paper disks

Wedelolactone Acts as Proteasome Inhibitor in Breast Cancer Cells

Copper ions regulate cytotoxicity of disulfiram to myeloid leukemia cells

Contact Info

Product

Resources

About